--- code/qcommon/vm_ppc.c.orig	2021-06-16 14:15:09 UTC
+++ code/qcommon/vm_ppc.c
@@ -1814,18 +1814,18 @@ Put this at end of file because gcc messes up debug li
 void AsmCall( void ) {
 asm (
      // pop off the destination instruction
-"    lwz		r12,0(r4)	\n"	// RG_TOP, 0(RG_OPSTACK)
-"    addi	r4,r4,-4		\n"	// RG_OPSTACK, RG_OPSTACK, -4 \n"
+"    lwz		12,0(4)	\n"	// RG_TOP, 0(RG_OPSTACK)
+"    addi	4,4,-4		\n"	// RG_OPSTACK, RG_OPSTACK, -4 \n"
 
     // see if it is a system trap
-"    cmpwi	r12,0			\n"	// RG_TOP, 0 \n"
+"    cmpwi	12,0			\n"	// RG_TOP, 0 \n"
 "    bc		12,0, systemTrap	\n"
 
     // calling another VM function, so lookup in instructionPointers
-"    slwi	r12,r12,2		\n"	// RG_TOP,RG_TOP,2
+"    slwi	12,12,2		\n"	// RG_TOP,RG_TOP,2
                         // FIXME: range check
-"    lwzx	r12, r8, r12		\n"	// RG_TOP, RG_INSTRUCTIONS(RG_TOP)	
-"    mtctr	r12			\n"	// RG_TOP
+"    lwzx	12, 8, 12		\n"	// RG_TOP, RG_INSTRUCTIONS(RG_TOP)	
+"    mtctr	12			\n"	// RG_TOP
 );
 
 #if defined(MACOS_X) && defined(__OPTIMIZE__)
@@ -1834,8 +1834,8 @@ asm (
 #else
     // Mac OS X Server and unoptimized compiles include a GCC AsmCall frame
     asm (
-"	lwz		r1,0(r1)	\n"	// pop off the GCC AsmCall frame
-"	lmw		r30,-8(r1)	\n"
+"	lwz		1,0(1)	\n"	// pop off the GCC AsmCall frame
+"	lmw		30,-8(1)	\n"
 );
 #endif
 
@@ -1845,53 +1845,53 @@ asm (
     // calling a system trap
 "systemTrap:				\n"
 	// convert to positive system call number
-"	subfic	r12,r12,-1		\n"
+"	subfic	12,12,-1		\n"
 
     // save all our registers, including the current link register
-"    mflr	r13			\n"	// RG_SECOND		// copy off our link register
-"	addi	r1,r1,-92		\n"	// required 24 byets of linkage, 32 bytes of parameter, plus our saves
-"    stw		r3,56(r1)	\n"	// RG_STACK, -36(REAL_STACK)
-"    stw		r4,60(r1)	\n"	// RG_OPSTACK, 4(RG_REAL_STACK)
-"    stw		r5,64(r1)	\n"	// RG_MEMBASE, 8(RG_REAL_STACK)
-"    stw		r6,68(r1)	\n"	// RG_MEMMASK, 12(RG_REAL_STACK)
-"    stw		r7,72(r1)	\n"	// RG_ASMCALL, 16(RG_REAL_STACK)
-"    stw		r8,76(r1)	\n"	// RG_INSTRUCTIONS, 20(RG_REAL_STACK)
-"    stw		r9,80(r1)	\n"	// RG_NUM_INSTRUCTIONS, 24(RG_REAL_STACK)
-"    stw		r10,84(r1)	\n"	// RG_VM, 28(RG_REAL_STACK)
-"    stw		r13,88(r1)	\n"	// RG_SECOND, 32(RG_REAL_STACK)	// link register
+"    mflr	13			\n"	// RG_SECOND		// copy off our link register
+"	addi	1,1,-92		\n"	// required 24 byets of linkage, 32 bytes of parameter, plus our saves
+"    stw		3,56(1)	\n"	// RG_STACK, -36(REAL_STACK)
+"    stw		4,60(1)	\n"	// RG_OPSTACK, 4(RG_REAL_STACK)
+"    stw		5,64(1)	\n"	// RG_MEMBASE, 8(RG_REAL_STACK)
+"    stw		6,68(1)	\n"	// RG_MEMMASK, 12(RG_REAL_STACK)
+"    stw		7,72(1)	\n"	// RG_ASMCALL, 16(RG_REAL_STACK)
+"    stw		8,76(1)	\n"	// RG_INSTRUCTIONS, 20(RG_REAL_STACK)
+"    stw		9,80(1)	\n"	// RG_NUM_INSTRUCTIONS, 24(RG_REAL_STACK)
+"    stw		10,84(1)	\n"	// RG_VM, 28(RG_REAL_STACK)
+"    stw		13,88(1)	\n"	// RG_SECOND, 32(RG_REAL_STACK)	// link register
 
     // save the vm stack position to allow recursive VM entry
-"    addi	r13,r3,-4		\n"	// RG_TOP, RG_STACK, -4
-"    stw		r13,0(r10)	\n"	//RG_TOP, VM_OFFSET_PROGRAM_STACK(RG_VM)
+"    addi	13,3,-4		\n"	// RG_TOP, RG_STACK, -4
+"    stw		13,0(10)	\n"	//RG_TOP, VM_OFFSET_PROGRAM_STACK(RG_VM)
 
     // save the system call number as the 0th parameter
-"    add		r3,r3,r5	\n"	// r3,  RG_STACK, RG_MEMBASE		// r3 is the first parameter to vm->systemCalls
-"    stwu	r12,4(r3)		\n"	// RG_TOP, 4(r3)
+"    add		3,3,5	\n"	// r3,  RG_STACK, RG_MEMBASE		// r3 is the first parameter to vm->systemCalls
+"    stwu	12,4(3)		\n"	// RG_TOP, 4(r3)
 
     // make the system call with the address of all the VM parms as a parameter
     // vm->systemCalls( &parms )
-"    lwz		r12,4(r10)	\n"	// RG_TOP, VM_OFFSET_SYSTEM_CALL(RG_VM)
-"    mtctr	r12			\n"	// RG_TOP
+"    lwz		12,4(10)	\n"	// RG_TOP, VM_OFFSET_SYSTEM_CALL(RG_VM)
+"    mtctr	12			\n"	// RG_TOP
 "    bcctrl	20,0			\n"
-"    mr		r12,r3			\n"	// RG_TOP, r3
+"    mr		12,3			\n"	// RG_TOP, r3
 
     // pop our saved registers
-"   	lwz		r3,56(r1)	\n"	// RG_STACK, 0(RG_REAL_STACK)
-"   	lwz		r4,60(r1)	\n"	// RG_OPSTACK, 4(RG_REAL_STACK)
-"   	lwz		r5,64(r1)	\n"	// RG_MEMBASE, 8(RG_REAL_STACK)
-"   	lwz		r6,68(r1)	\n"	// RG_MEMMASK, 12(RG_REAL_STACK)
-"   	lwz		r7,72(r1)	\n"	// RG_ASMCALL, 16(RG_REAL_STACK)
-"   	lwz		r8,76(r1)	\n"	// RG_INSTRUCTIONS, 20(RG_REAL_STACK)
-"   	lwz		r9,80(r1)	\n"	// RG_NUM_INSTRUCTIONS, 24(RG_REAL_STACK)
-"   	lwz		r10,84(r1)	\n"	// RG_VM, 28(RG_REAL_STACK)
-"   	lwz		r13,88(r1)	\n"	// RG_SECOND, 32(RG_REAL_STACK)
-"    addi	r1,r1,92		\n"	// RG_REAL_STACK, RG_REAL_STACK, 36
+"   	lwz		3,56(1)	\n"	// RG_STACK, 0(RG_REAL_STACK)
+"   	lwz		4,60(1)	\n"	// RG_OPSTACK, 4(RG_REAL_STACK)
+"   	lwz		5,64(1)	\n"	// RG_MEMBASE, 8(RG_REAL_STACK)
+"   	lwz		6,68(1)	\n"	// RG_MEMMASK, 12(RG_REAL_STACK)
+"   	lwz		7,72(1)	\n"	// RG_ASMCALL, 16(RG_REAL_STACK)
+"   	lwz		8,76(1)	\n"	// RG_INSTRUCTIONS, 20(RG_REAL_STACK)
+"   	lwz		9,80(1)	\n"	// RG_NUM_INSTRUCTIONS, 24(RG_REAL_STACK)
+"   	lwz		10,84(1)	\n"	// RG_VM, 28(RG_REAL_STACK)
+"   	lwz		13,88(1)	\n"	// RG_SECOND, 32(RG_REAL_STACK)
+"    addi	1,1,92		\n"	// RG_REAL_STACK, RG_REAL_STACK, 36
 
     // restore the old link register
-"    mtlr	r13			\n"	// RG_SECOND
+"    mtlr	13			\n"	// RG_SECOND
 
     // save off the return value
-"    stwu	r12,4(r4)		\n"	// RG_TOP, 0(RG_OPSTACK)
+"    stwu	12,4(4)		\n"	// RG_TOP, 0(RG_OPSTACK)
 
 	// GCC adds its own prolog / epliog code
  );